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>source_estim_GG_from_histo</H1
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NAME="AEN11391"
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><H2
>Name</H2
>source_estim_GG_from_histo&nbsp;--&nbsp;estimate the parameters of a generalized Gaussian</DIV
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><H2
>Synopsis</H2
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><P
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include &lt;it/source_fit.h&gt;
      </PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>void source_estim_GG_from_histo</CODE
>( vec pdf, vec symbols, double * alpha, double * beta
        );</CODE
></P
><P
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><H2
>DESCRIPTION</H2
><P
>This function estimates the parameters of a generalized Gaussian distribution (GGD) by minimizing the Kullback-Leibler distance between the estimated GGD and the histogram <CODE
CLASS="PARAMETER"
>pdf</CODE
>. The values associated to each symbol of the alphabet are given in <CODE
CLASS="PARAMETER"
>symbols</CODE
>. Therefore, <CODE
CLASS="PARAMETER"
>symbols</CODE
> has the same size as <CODE
CLASS="PARAMETER"
>pdf</CODE
>, which must sum to one. The estimated alpha and beta parameters of the GGD are returned at the address pointed by the <CODE
CLASS="PARAMETER"
>alpha</CODE
> and <CODE
CLASS="PARAMETER"
>beta</CODE
> arguments. These arguments are also used as the initial GGD parameters for the minimization.</P
><P
>The generalized Gaussian distribution is defined as GGD(x) = exp(-(|x| / <CODE
CLASS="PARAMETER"
>alpha</CODE
>)**<CODE
CLASS="PARAMETER"
>beta</CODE
>).</P
><H2
>RETURN VALUE</H2
><P
>    
   </P
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